Limited energy resources and the growing demand to decrease greenhouse gas emissions have intensified research of carbon-free energy sources. Batteries that store high-energy densities play a large role in implementation of green energy technologies and non-petroleum vehicular mobility. To date, rechargeable Li-ion batteries (LIBs) offer the highest energy density of any battery technology, and are expected to provide a solution for our future energy-storage requirements. Unfortunately, LIBs have a number of limitations, such as capacity loss over time during long-term cycling due to phase transitions leading to detrimental volume changes in the electrode materials. The energy density of LIBs must be improved in order for the adoption of the technology to be more widespread and economically compelling. One reason LIBs do not provide sufficient energy density is because the electrodes, both the negative electrode (anode), typically graphite, and the positive electrode (cathode), typically, layered LiMO2 (M=Mn, Co, Ni), spinel LiMn2O4 and olivine LiFePO4, do not offer sufficient capacity or a high enough electrochemical potential to meet energy demands. Thus, there is an increasing need for new LIB technologies to provide higher energy densities than are currently available.
Silicon is considered to be a promising next-generation anode material for LIBs due to its large energy density and natural abundance. However large volume change and poor stability with electrolytes are problems that must still be resolved. Silicon monoxide is considered as an alternative to graphite and silicon to meet the high energy requirements for LIBs. Compared to commercial graphite electrodes, silicon monoxide electrodes offer significantly higher capacity. However, large irreversible capacity loss (ICL) and a limited cycle life for silicon monoxide reduce the energy output and efficiency of the cell, thereby compromising the management of cell/battery operation.
There is an ongoing need for new electrode materials to ameliorate the problems associated with the ICL and limited cycle life of silicon monoxide. The electrodes and electrode materials described herein address this need.